For me, it's a complete waste of a mechanic. To me it seems they just added it for the lulz "because we can" and then did nothing with it. The whole marriage, having children/forming a family system is terrible and underwhelming. It lacks soo much depth, so much dialog, so much interaction, that having a child and then playing as them is just a pure cosmetic feature in the end. If they expanded it, made the children age faster, add more interaction with them (you can't even see them until they grow up?? Damn nice absent parents we are in this game lol), maybe it would be an interesting RPG mechanic, right now it's useless